Kelly bushing



W. A. ABEGG KELLY BUSHING July 3, 1951 2 Sheets-Sheet 1 Filed March 17, 1947 INVENTORv WATER 14. 4556c;

J l I" ATTORNEYS.

July 3, 195] w, ABEGG 2,558,806

KELLY BUSHING Filed March 17, 1947 2 Sheets-Shet 2 INVENTOR.

ATTORNEYS.

Patented July 3, 1951 UNITED STATES PATENT OFFICE KELLY BUSHING Walter A. Abegg, Los Angeles, Calif., assignor, by mesne assignments, to Abegg & Reinhold 00., Los Angeles, Calif a corporation of California Application March 1'7, 1947, Serial No. 735,152

14 Claims. ll

This invention relates to well drilling equipment, and particularly pertains to a Kelly bushing.

In the operation of well drilling equipment a Kelly bushing is used to provide a driving connection between the rotary table of a rotary well drilling rig and the Kelly bar or drill stem of a string of drill pipe. As is well known, the kelly is usually square in cross-section and extends through a bushing fitted with faces or members designed to engage faces on the kelly, and to impart positive rotation from the bushing to the kelly while permitting vertical movement of the kelly through the bushing. In the design of Kelly bushings it is has been common practice to make the bushings in parts which are split along vertical planes, and which parts hold kelly engaging elements in position. In view of the fact that the torque strains incident to the driving action between the Kelly bushing and the kelly are in a plane normal to the plane or planes along which the Kelly bushing is divided, it is obvious that a force of large magnitude will be imposed upon the fastening means, and that often the parts will become loosened. It has also been common practice in the design of Kelly bushings to dispose the area of contact between the bushing and the kelly in a plane above the top of the rotary table within which the bushing is mounted. Thus, when the rotary table is driven at high speed there is a tendency for the bushing to rock as moments of force will be created alternately above and below the top of the rotary table, with the result that the Kelly bushing will tend to climb up the Kelly bar and cut of the bowl in the rotary table. It is the principal object of the present invention, therefore, to provide a Kelly bushing in which vertical parting lines have been eliminated, thereby insuring a maximum strength in the body of the bushing and in which the point of contact between elements of the Kelly bushing and the Kelly bar will be in a plane below the top of the rotary table, this plane being along a horizontal parting line in the bushing, thus insuring maximum strength in the Kelly bushing and eliminating the tendency of the bushing to climb out of its seat.

It is a further object of the present invention to provide a Kelly bushing having anti-friction rollers for engaging the kelly, the axes of said rollers being in a horizontal plane and the length of the rollers extending transversely of the faces of the kelly.

The present invention contemplates the provision of a kelly bushing formed by two comple- 2 mentary halves which are assembled together along a horizontal parting line and between which halves anti-friction kelly engaging rollers are supported upon axes disposed in a plane normal to the vertical axis of the kelly.

The invention is illustrated by Way of example in the accompanying drawings, in which:

Figure 1 is a view in vertical section and elevation showing the application of the Kelly bushing to a kelly and a rotary table.

Fig. 2 is an enlarged view in horizontal section as seen on the line 2-2 of Fig. 1 and shows the construction of the Kelly bushing.

Fig. 3 is a view in transverse section through the Kelly bushing as seen on the line 3-3 of Fig. 2 and shows the construction and arrangement of the rollers and the manner in which they are mounted between the horizontally separable halves of the bushing.

Referring more particularly to the drawings, It! indicates a rotary table having the usual bore II to receive structures such as a Kelly bushing l2, with which the present invention is concerned. The Kelly bushing l2 fits within the bore and rotates positively therewith. A central opening through the bushing receives a kelly l3 which is here shown as being square insection.

The Kelly bushing I2 is made in complementary sections I l and I5. These sections are square along their horizontal perimeters so that they will fit into the bowl of the rotary table and will be held positively to rotate with the table. The lower section [4 is formed with a horizontal parting face I 6 which is in a plane at right angles to the center of the bushing and upon which the horizontal parting face I! of the upper sec tion it rests. The bushing sections 14 and [5 are formed at their corners with longitudinally aligned bores l8 and I9 to receive bolts 26. The bores l9 are formed with a counterbore 2! within which a head 22 of the bolts 20 seats. The head 22 is formed with a plurality of side faces, and the counterbore 2| is similarly formed so that the bolt will be held against rotation. The upper end of each of the bolts is fitted with a castellated nut 23 by which the lower and upper Kelly bushing sections 14 and 15 may be firmly clamped together. The Kelly bushing section I5 is formed with an upper annular lip 24 which reinforces the entire structure. The lip '24 is for-med'with an inner circular wall 25 of a diameter which attends a desired amount of play from the corner-tocorner diagonal line extending from the theoretical corners of the kelly I3. Formed in the complementary horizontal flat faces 16 and Fl of the upper and lower bushing sections are semicircular grooves 26 and 21 which combine to form circular bores to receive the opposite ends of roller pins 28. The roller pins 28 are clamped into position between the bushing sections I4 and I5 and span a complementary recess 29 formed in the side walls of the bushing and communicates with the central bore 25. The number of pins 28 and the number of recesses 29 agree with the number of sides of the kelly to be engaged by the Kelly bushing. The 'side walls 30 of the recesses 29 are arcuate and are concentric with the axes of the roller pins 28. The end walls, as indicated at 3:5, are flat and parallel and lie in planes parallel to the axes of the pins 28. Mounted within the re cess 29 and upon the pins 28 are rollers 32. These rollers are cylindrical members having a length agreeing substantially with the overall width of the faces 33 on the kelly l3. The rollers are formed with a center bore 34 which is of a diameter considerably larger than the diameter of the pins 28. At the opposite ends of the bore 34 antifriction bearing structures 35 are mounted. These structures are interposed between the cylindrical surface of the pins 28 and the bore 35. A spacing bushing 36 is. disposed between the anti-friction bearings 35. Retaining washers 37 are mounted within the counterbores 38 at the opposite ends of the bore 34 of the rollers 32 and fit upon the roller pins 28. By reference to Fig. 2 of the drawing, it will be seen that the rollers 32 are arranged so that they will provide longitudinal contact faces which engage the flat faces 33 of the kelly in a common horizontal plane.

In explaining the operation of the present invention it should be emphasized that the Kelly bushing here disclosed is materially cheaper in construction than ordinary Kelly bushings which are hinged in order to be disposed in an embracingposition around the kelly, and that the structure is so simple and inexpensive as to make it practical for a Kelly bushing, as here shown, to be assembled upon a kelly of a particular size and to remain on that kelly until the structure is worn out. This will provide many advantages, such as cheapness in construction, the provision of a rugged structure which is not easily broken, the elimination of the machine work required to provide hinges and latches, and the provision of a Kelly bushing which will remain firmly in its seat regardless of the speed at which the rotary table is driven.

In operation of the present invention the structure is made as shown in the drawing, after which the kelly 13 is inserted through the upper section l5 of the bushing. The rollers 32 are then placed within the recessed portions 29 in the upper bushing section 15 and the roller pins 2 8 are positioned within the semicircular recesses 2| of the upper bushing section, it being understood that when this assembly is performed the rollers will lie in a plane normal to the central axis of the kelly with the cylindrical surfaces of the rollers 32 making line contact with the faces of the kelly across the width thereof. The lower bushing section I4 is then placed in position and the nuts 23 are applied to the bolts 20. When the nuts 23 are tightened it is obvious that the roller pins 23 will be gripped between the semicircular recesses 26 and 21 of the upper and lower bushing sections Id and I5, respectively, and that the bushing may then be placed in its seated position within the bowl of the rotary table ill. By reference to Fig. 1 it will be seen that the plane of the axes of the rollers will assume a position 4 below the upper face of the rotary table so that there will be no tendency for vibration to take place between the bushing and the kelly. It will also be recognized that the rollers 32 will have line contact with the flat faces of the kelly, which contact will extend across the flat faces and will be in a common horizontal plane within the confines of the Kelly bushing seat. This will insure that the pressure will be uniformly imparted from the rollers to the kelly, and that the kelly may move freely between the rollers. This is in contra-distinction to the action obtained by the usual construction in which the axes of the Kelly bushing rollers or inserts extend vertically and tend to impinge into the surfaces of the flat faces of the kelly.

In the foregoing description the members contacting the faces of the kelly have been described as being cylindrical rollers, the horizontal axes of which are parallel to the faces of the kelly and lie in a common plane normal to the central axis of the kelly. It is to be understood that solid blocks may be mounted between the two sections Hi and 15 of the bushing as substitutes for the rollers, and that if desired these blocks may be faced with Stellite or may carry inserts of carbaloy which contact the surfaces of the kelly and perform the same function as the rollers 32.

In the drawings the Kelly bushing is shown as seated directly within the square bore H formed in a rotary table. It is to be understood that this arrangement is shown by way of example and that it may be preferable to provide a standard master bushing which seats in the table and within which the Kelly bushing would be positioned.

It will thus be seen that the Kelly bushing here disclosed is not only simple and inexpensive in construction but that it is rugged and will not be easily broken, and that furthermore it provides anti-friction rollers which operate in a horizontal plane normal to the vertical axis of the kelly, and which structure may be parted along a horizontal plane in the event it is necessary to replace or repair the rollers.

While I have shown the preferred form of my invention as now known to me, it will be understood that various changes may be made in combination, construction and arrangement of parts by those skilled in the art, Without departing from the spirit of the invention as claimed. 7

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

l. A Kelly bushing having an outer configuration to seat within and positively engage a rotary table and being formed with a central opening therethrough to accommodate a, kelly, said bush-.

ing being formed in two complementary sections abutting each other along a, plane normal to the central axis of the bushing, complementary re cesses in the abutting faces of said sections accommodating roller pins and rollers, the axes of which lie in the parting plane of the two sections with the roller disposed with longitudinal contacting faces in engagement with the faces of the kelly, said contacting faces lying along chords of the circle defining the opening through the bushing, and means securing said bushing sections together.

2. A Kelly bushing comprising a pair of complementary bushing sections, square in perimeter and having a parting line in a plane normal to the central axis of the bushing, said bushing being formed with a central opening therethrough ac 5. commodating a kelly, complementary recesses formed in the bushing sections and in the wall of said circular opening, said recesses agreeing in number and relative position with faces of the kelly, Kelly rollers, one disposed Within each of said recesses with its longitudinal axis extending transversely of and parallel to a face of the kelly and projecting into said opening to present a longitudinal contact edge extending across a face of the kelly, a plurality of roller pins rotatably mounting said rollers respectively, said pins being seated within complementary recesses in the contiguous faces of the bushing sections, and means holding the bushing sections in their assembled relationship and holding the roller pins in their seated positions.

3. A Kelly bushing comprising a pair of complementary bushing sections, square in perimeter and having a parting line in a plane normal to the central axis of the bushing, said bushing being formed with a central opening therethrough accommodating a kelly, complementary recesses formed in the bushing sections and in the wall of said circular opening, said recesses agreeing in number and relative position with faces of the kelly, cylindrical Kelly rollers, one disposed within each of said recesses with its longitudinal axis extending transversely of and parallel to a face of the kelly and projecting into said opening to present a longitudinal contact edge extending across a face of the kelly, a plurality of roller pins rotatably mounting said rollers respectively, said pins being seated within complementary recesses in the contiguous faces of the bushing sections, and means holding the bushing sections in their assembled relationship and holding the roller pins in their seated positions.

4. A Kelly bushing having an outer configuration to seat within and positively engage a rotary table, said bushing comprising a pair of superposed complementary sections each having an axial bore of a size to receive a kelly endwise therein, said sections having complementary recesses in their adjacent faces, a roller mounted in each of said recesses for rotation about an axis lying in a plane normal to the axis of rotation of the bushing and projecting into said bore to have rolling torque engagement with a kelly inserted in the bushing, and removable fastening means securing the bushing sections together and the rollers in said recesses.

5. A Kelly bushing having an outer configuration to seat within and positively engage a rotary table, said bushing comprising a pair of superposed sections fitted together on a plane transverse to their axes of rotation and having aligned bores therethrough adapted to receive a kelly endwise therein, one of said sections having a recess opening into the plane of juncture of said sections, a roller mounted on a pin, the ends of the pin projecting beyond the roller, the ends of the pin being fitted closely in said recess with the pin axis in a plane normal to the axis of rotation of the bushing, the periphery of the roller extending into the bore of the bushing to have rolling torque engagement with a face of a kelly inserted in the bore, and means securing the bushing sections together.

6. Rotary driliing apparatus comprising a rotary table adapted to rotate about a vertically extending axis and containing a vertically extending opening, and a Kelly bushing including a body having a portion receivable within said opening in the rotary table and having an outer surface of non-circular horizontal section engageable with a corresponding non-circular wall of the table opening to rotatively interconnect the table and bushing, said bushing body containing a central vertically extending opening through which a non-circular kelly may extend, said body comprising a pair of separately formed sections positioned one above the other engaging at a location beneath the top of the table and each engaging the table within said opening therein, fastening means retaining said sections against vertical separating movement, and a plurality of kelly engaging members retained between the sections at locations about said opening in the body and each projecting into said opening to engage a corresponding face of the kelly in driving relation thereto.

7. Rotary drilling apparatus comprising a rotary table adapted to rotate about a vertically extending axis and containing a non-circular opening, and a Kelly bushing including a body having a non-circular portion receivable Within said opening in the rotary table to be driven thereby and containing a central opening through which a non-circular kelly may extend, said body comprising a pair of separately formed sections positioned one above the other engaging at a location beneath the top of said table and each engaging the table Within said non-circular opening, fastening means retaining said sections against vertical separating movement, a plurality of horizontaily extending shafts mounted between the sections at locations about said opening in the body and a plurality of rollers mounted by said shafts respectively for rotation about horizontally extending axes within recesses in said body and each projecting into said opening in the body to engage a corresponding face of the kelly in driving relation thereto.

8. Rotary drilling apparatus comprising a rotary table adapted to rotate about a vertically extending axis and containing a non-circular opening, and a Kelly bushing including a body having a noncircular portion receivable within said opening in the rotary table to be driven thereby and containing a central opening through which a non-circular kelly may extend, said body comprising a pair of separately formed sections positioned one above the other engaging in a horizontal plane at a location beneath the top of said table and each engaging the table within said non-circular opening, fastening means retaining said sections against vertical separating movement, a plurality of horizontally extending shafts mounted between the sections at locations about said opening in the body, said shafts being received within complementary recesses in the opposed faces of the body sections and having their axes extending in said plane, and a plurality of rollers mounted by said shafts respectively within central enlarged portions of said recesses for rotation about said axes and each projecting into said opening in the bushing body to engage a corresponding face of the kelly in driving relation thereto.

9. A Kelly bushing comprising a body containing a central opening through which a non-circular kelly may extend vertically, said body including two separately formed sections positioned one above the other, fastening means for retaining said sections against vertical separating movement, said sections having outer vertically extending surfaces of corresponding polygonal horizontal section and each extending substantially entirely about the corresponding section, said surfaces of the two sections being alined so 7 that they may simultaneously engage th'inner polygonal wall of a rotary table for simultaneous transmission of rotary motion from the table to both sections, and a plurality of Kelly engaging members retained between the sections at 10- cations about said opening in the body and each projecting into said opening to engage a corresponding face of the kelly in driving relation thereto.

10. A Kelly bushing comprising a body containing a'central opening through which a non-circular kelly may extend vertically, said body including two separately formed sections positioned one above the other, fastening means for retaining said sections against vertical separating movement, said sections having outer vertically extending surfaces of corresponding polygonal horizontal section and each extending substantially entirely about the corresponding section, said surfaces of the two sections being alined so that they may simultaneously engage the inner polygonal wail of a rotary table for simultaneous transmission of rotary motion from the table to both sections, and a plurality of rollers mounted between the body sections in recesses in the body and for rotation about horizontally extending axes, said rollers being positioned about said opening in the body and projecting into said opening to each, engage a corresponding face of the kelly in driving relation thereto.

11. A Kelly bushing comprising a body containing a central opening through which a noncircular kelly may extend vertically, said body including two separately formed sections positioned one abovethe other and meeting along' a horizontal plane, fastening means for retaining said sections against vertical separating movement, said sections having outer vertically extending surfaces of corresponding polygonal horizontal section and each extending substantially entirely about the corresponding section, said surfaces of the two sections meeting and being alined at said plane so that they may simultaneously engage the inner polygonal wall of a rotary table for simultaneous transmission of rotary motion from the table to both sections, and a plurality of rollers mounted between the body sections in recessesin the body and for rotation about horizontally extending axes, said rollers being positioned about said opening in the body and projecting into said opening to each engage a corre-:

'sponding face of the kelly in driving relation thereto.

12. A Kelly bushing comprising a body containing a central opening through which a noncircular kelly may extend vertically, said body including two separately formed sections positioned one above the other and meeting along a horizontal plane, fastening means for retaining said sections against vertical separating movement, said sections having outer vertically extending surfaces of corresponding polygonal horizontal section and each extending substantially entirely about the corresponding section, said surfaces of the two sections meeting and being alined at said plane, so that they may simultaneously engage the inner polygonal wall of a rotary table for simultaneous transmission of rotary motion from the table to both sections, a plurality of shafts extending horizontally between the sections, said shafts being mounted within com lementary recesses in the opposed faces of the body sections and having their axes extending in said plane, and a plurality of rollers mounted by said shafts respectively within central enlarged portions of said recesses for rotation about said axes and each projecting into said opening in the bushing body to engage a corresponding face of the kelly in driving relation thereto.

13. A Kelly bushing comprising a body having a portion with a non-circular vertically extending outer surface receivable within a non-circular opening in a rotary table to be driven thereby, said body comprising a pair of separately formed sections positioned one above the other, fastening means retaining said sections against vertical separating movement, a plurality of horizontally extending shafts retained between the sections at locations about said opening in the body, said shafts being received within complementary recesses in the opposed faces of the body sections, a plurality of rollers mounted by said shafts Within central enlarged portions of said recesses for rotation about horizontally extending axes and each projecting into said opening in the bushing body to engage a, corresponding face of the kelly in driving relation thereto, each of said rollers having a pair of annular transverse surfaces at its opposite ends, said body sections forming together at the opposite ends of the enlarged central portion of each recess a pair of transverse annular shoulders, and a plurality of annular thrust bearings received between and engaging said shoulders respectively and said end surfaces of the rollers to locate the rollers axially along the shafts. V

14. A Kelly bushing comprising a body having a portion with an outer surface of non-circular horiozntal section for reception with a non-circular opening in a rotary table to be driven thereby, said body containing a central opening through which a non-circular kelly may extend vertically, a plurality of shafts extending horizontally within recesses in said body at locations about said opening, a plurality of rollers mounted by said shafts respectively within central enlarged portions of said recesses for rotation about horizontally extending axes and each projecting into said opening in the body to engage a corresponding face of the kelly in driving relation thereto, a pair of annular xially spaced anti-friction bearing assemblies received radially between each of said shafts and the corresponding roller, and an annular ring between said bearing assemblies and spacing them apart.

' WALTER A. ABEGG.

REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS 

